The department shared a letter to FBI Director Christopher Wray stating Suiter was scheduled to testify in a federal police corruption case the day after he was shot and killed on Nov. 15.

"The circumstances surrounding Detective Suiter's killing are significantly complicated by the fact taht he was to appear before a federal grand jury the following day," Police Commissioner Kevin Davis wrote. "I am growing increasingly uncomfortable that my homicide detectives do not know all of the facts known to the FBI or USAO that could, if revealed to us, assist in furthering the murder investigation."

Suiter, 43, died at Maryland Shock and Trauma a day after he was shot in the head after approaching a suspicious man while investigating a 2016 triple homicide in the West Baltimore neighborhood of Harlem Park.

It was later revealed he was shot with his own firearm and while police department officials have said there was a violent struggle leading up to the shooting, police have also been investigating a theory Suiter's death was the result of a suicide.

The FBI has yet to respond to the Baltimore Police Department since it sent its request on Friday.

Baltimore Mayor Catherine Pugh and other local leaders including Lt. Gene Ryan -- president of the local police union -- have also called on the FBI to take over the investigation claiming the department's homicide detectives are still mourning Suiter's death.

"I just think they're too close to the investigation. It's too personal. They might miss something unintentionally," Ryan said. "It's like me investigating my own brother being killed. When you're hitting this close to home, it has a different impact."

Davis said his detectives can't properly investigate the case amid a perception they don't possess all of the necessary information.

He added the community "needs to know that I am willing, and this Police Department is willing, to invite any extra sets of eyes or resources ... to look at this incident to try to figure it out."